[flang-commits] [flang] [flang][semantics] ensure defined io dummies are not arrays. (PR #162744)

[Andre Kuhlenschmidt via flang-commits]

https://github.com/akuhlens created https://github.com/llvm/llvm-project/pull/162744

fixes [#162709](https://github.com/llvm/llvm-project/issues/162709)

>From 6e1e15ad9c2ef2ea580f95baf743a87b8f2a7343 Mon Sep 17 00:00:00 2001
From: Andre Kuhlenschmidt <akuhlenschmi at nvidia.com>
Date: Thu, 9 Oct 2025 14:47:40 -0700
Subject: [PATCH] initial commit

---
 flang/lib/Semantics/check-declarations.cpp |  2 ++
 flang/test/Semantics/io11.f90              | 21 +++++++++++++++++++++
 2 files changed, 23 insertions(+)

diff --git a/flang/lib/Semantics/check-declarations.cpp b/flang/lib/Semantics/check-declarations.cpp
index 75934243b7916..8cb0d3335c616 100644
--- a/flang/lib/Semantics/check-declarations.cpp
+++ b/flang/lib/Semantics/check-declarations.cpp
@@ -3623,6 +3623,7 @@ void CheckHelper::CheckDioDtvArg(const Symbol &proc, const Symbol &subp,
                 ioKind == common::DefinedIo::ReadUnformatted
             ? Attr::INTENT_INOUT
             : Attr::INTENT_IN);
+    CheckDioDummyIsScalar(subp, *arg);
   }
 }
 
@@ -3688,6 +3689,7 @@ void CheckHelper::CheckDioAssumedLenCharacterArg(const Symbol &subp,
           "Dummy argument '%s' of a defined input/output procedure must be assumed-length CHARACTER of default kind"_err_en_US,
           arg->name());
     }
+    CheckDioDummyIsScalar(subp, *arg);
   }
 }
 
diff --git a/flang/test/Semantics/io11.f90 b/flang/test/Semantics/io11.f90
index c00deede6b516..6bb7a71f0defc 100644
--- a/flang/test/Semantics/io11.f90
+++ b/flang/test/Semantics/io11.f90
@@ -809,3 +809,24 @@ subroutine wf(dtv, unit, iotype, v_list, iostat, iomsg)
     end
   end interface
 end
+
+module m30
+    type base
+        character(5), allocatable :: data
+    end type
+    interface write(formatted)
+        subroutine formattedRead (dtv, unit, iotype, v_list, iostat, iomsg)
+        import base
+            !ERROR: Dummy argument 'dtv' of a defined input/output procedure must be a scalar
+            class (base), intent(in) :: dtv(10)
+            integer, intent(in) :: unit
+            !ERROR: Dummy argument 'iotype' of a defined input/output procedure must be a scalar
+            character(*), intent(in) :: iotype(2)
+            integer, intent(in) :: v_list(:)
+            !ERROR: Dummy argument 'iostat' of a defined input/output procedure must be a scalar
+            integer, intent(out) :: iostat(*)
+            !ERROR: Dummy argument 'iomsg' of a defined input/output procedure must be a scalar
+            character(*), intent(inout) :: iomsg(:)
+        end subroutine
+    end interface
+end module